Fluorescent substrate, display apparatus, and lighting apparatus

Abstract

A fluorescent substrate includes a substrate, a fluorescent layer disposed on the substrate, the fluorescent layer emitting fluorescence owing to excitation light passing through an incident surface of the fluorescent layer facing the substrate and emitting the fluorescence through an exit surface of the fluorescent layer facing the incident surface, and reflective portions, which face the incident surface and side surfaces of the fluorescent layer in contact with the incident surface. The reflective portions include a first reflective portion that reflects the excitation light and the fluorescence and a second reflective portion disposed on at least part of the incident surface, the second reflective portion allowing at least light having a peak wavelength of the excitation light to pass through and reflecting at least light having a peak wavelength of the fluorescence.

1 . A fluorescent substrate, comprising:
 a substrate;   a fluorescent layer disposed on the substrate, the fluorescent layer emitting fluorescence owing to excitation light passing through an incident surface of the fluorescent layer facing the substrate and emitting the fluorescence through an exit surface of the fluorescent layer facing the incident surface, the incident surface including a first portion and a second portion, the excitation light passing through the second portion; and   reflective portions, which face the incident surface and side surfaces of the fluorescent layer in contact with the incident surface,   wherein the reflective portions include a first reflective portion that is disposed on the side surfaces and the first portion of the incident surface and reflects the excitation light and the fluorescence and   a second reflective portion disposed on the second portion of the incident surface the second reflective portion allowing at least light having a peak wavelength of the excitation light to pass through and reflecting at least light having a peak wavelength of the fluorescence.   
     
     
         2 . The fluorescent substrate according to  claim 1 , wherein
 the fluorescent layer includes a plurality of fluorescent layers each disposed in a predetermined region on the substrate,   a partition surrounding each of the plurality of fluorescent layers is disposed on a surface of the substrate, and   the first reflective portion is disposed on at least side surface of the partition.   
     
     
         3 . The fluorescent substrate according to  claim 2 , wherein the partition is formed of the material of the first reflective portion. 
     
     
         4 . The fluorescent substrate according to  claim 2 , wherein the length from the surface of the substrate to the top of the partition is larger than the thickness of the fluorescent layer. 
     
     
         5 . The fluorescent substrate according to  claim 1 , wherein the first reflective portion is disposed on a side surface of the fluorescent layer. 
     
     
         6 . The fluorescent substrate according to  claim 1 , wherein the second reflective portion allows 50% or more of the light having a peak wavelength of the excitation light to pass through. 
     
     
         7 . The fluorescent substrate according to  claim 1 , further comprising a planarization layer on the incident surface of the fluorescent layer, wherein the second reflective portion is disposed on the planarization layer. 
     
     
         8 . The fluorescent substrate according to  claim 1 , wherein the fluorescent layer contains an inorganic fluorescent substance. 
     
     
         9 . The fluorescent substrate according to  claim 1 , wherein the second reflective portion is a dielectric multilayer film. 
     
     
         10 . The fluorescent substrate according to  claim 1 , wherein the second reflective portion is a thin silver film. 
     
     
         11 . A display apparatus, comprising a fluorescent substrate and a light source,
 wherein the fluorescent substrate includes   a substrate,   a fluorescent layer disposed on the substrate, the fluorescent layer emitting fluorescence owing to excitation light passing through an incident surface of the fluorescent layer facing the substrate and emitting the fluorescence through an exit surface of the fluorescent layer facing the incident surface, the incident surface including a first portion and a second portion, the excitation light passing through the second portion, and   reflective portions, which face the incident surface and side surfaces of the fluorescent layer in contact with the incident surface,   wherein the reflective portions include a first reflective portion that is disposed on the side surfaces and the first portion of the incident surface and reflects the excitation light and the fluorescence and   a second reflective portion disposed on the second portion of the incident surface, the second reflective portion allowing at least light having a peak wavelength of the excitation light to pass through and reflecting at least light having a peak wavelength of the fluorescence, and   the light source includes a light-emitting device for emitting ultraviolet light as excitation light with which the fluorescent layer is irradiated.   
     
     
         12 . The display apparatus according to  claim 11 , further comprising:
 a plurality of pixels, including a red color pixel for displaying an object with red light, a green color pixel for displaying an object with green light, and a blue color pixel for displaying an object with blue light,   wherein the fluorescent layer includes a red fluorescent layer for emitting red light utilizing the ultraviolet light as the excitation light in the red color pixel, a green fluorescent layer for emitting green light utilizing the ultraviolet light as the excitation light in the green color pixel, and a blue fluorescent layer for emitting blue light utilizing the ultraviolet light as the excitation light in the blue color pixel.   
     
     
         13 . A display apparatus, comprising a fluorescent substrate and a light source,
 wherein the fluorescent substrate includes   a substrate,   a fluorescent layer disposed on the substrate, the fluorescent layer emitting fluorescence owing to excitation light passing through an incident surface of the fluorescent layer facing the substrate and emitting the fluorescence through an exit surface of the fluorescent layer facing the incident surface, the incident surface including a first portion and a second portion, the excitation light passing through the second portion, and   reflective portions, which face the incident surface and side surfaces of the fluorescent layer in contact with the incident surface,   wherein the reflective portions include a first reflective portion that is disposed on the side surfaces and the first portion of the incident surface and reflects the excitation light and the fluorescence and   a second reflective portion disposed on the second portion of the incident surface, the second reflective portion allowing at least light having a peak wavelength of the excitation light to pass through and reflecting at least light having a peak wavelength of the fluorescence, and   the light source includes a light-emitting device for emitting blue light as excitation light with which the fluorescent layer is irradiated.   
     
     
         14 . The display apparatus according to  claim 13 , further comprising:
 a plurality of pixels, including a red color pixel for displaying an object with red light, a green color pixel for displaying an object with green light, and a blue color pixel for displaying an object with blue light,   wherein the fluorescent layer includes a red fluorescent layer for emitting red light utilizing the blue light as the excitation light in the red color pixel and a green fluorescent layer for emitting green light utilizing the blue light as the excitation light in the green color pixel, and   the blue color pixel includes a scattering layer for scattering the blue light.   
     
     
         15 . The display apparatus according to  claim 12  or  14 , wherein the light source is an active-matrix drive light source, which includes a light-emitting device for each of the plurality of pixels and a driver device for driving the light-emitting device. 
     
     
         16 . The display apparatus according to  claim 15 , wherein light is extracted from a surface of the substrate opposite the plurality of driver devices. 
     
     
         17 . The display apparatus according to  claim 11  or  13 , wherein the light source is one of light-emitting diodes, organic electroluminescent devices, and inorganic electroluminescent devices. 
     
     
         18 . The display apparatus according to  claim 12  or  14 , wherein the light source is a planar light source for emitting light through a light exit surface, and each of the pixels includes a liquid crystal device between the planar light source and the fluorescent substrate, the liquid crystal device controlling the transmittance of light emitted from the planar light source. 
     
     
         19 . (canceled)